GE Café Refrigerator: Loud Thumping Noise During Defrost... | appliancefaults.com

Technical Background:

The refrigerator's Main Control Unit (MCU) initiates the defrost cycle at predetermined intervals. During defrost, the defrost heater is energized, and the evaporator fan should ideally shut off. The evaporator fan motor is a DC motor controlled by the MCU, which sends a 12V DC signal to operate the fan. The thermistor provides feedback to the MCU regarding the evaporator temperature.

Symptoms:

The homeowner observes a loud thumping noise emanating from the freezer compartment during the defrost cycle of their GE Café refrigerator. The noise subsides after the defrost cycle completes.

Possible Causes:

Ice buildup obstructing the evaporator fan blades.
Defective evaporator fan motor.
Loose fan blade on the motor shaft.
Wiring harness contacting the fan blade or housing.
Failed defrost thermostat.
Damaged evaporator fan blade.

Solution:

1

Unplug the refrigerator from the outlet or turn off the breaker to the refrigerator circuit.
2

Remove the evaporator cover inside the freezer compartment, typically secured with screws (use a 1/4-inch nut driver).
3

Visually inspect the evaporator fan for ice buildup. If present, manually defrost the ice using a hair dryer on a low setting or allow it to melt naturally.
4

Check the fan blade for any damage or obstructions. Ensure the fan blade is securely attached to the motor shaft.
5

If no ice is present and the fan blade is secure, use a multimeter to test the evaporator fan motor for continuity. If there is no continuity, the motor is likely defective.
6

Check the wiring harness to the evaporator fan motor for any loose connections or damage. Repair or replace as needed.
7

If the fan motor receives power (typically 12V DC) and does not run, replace the evaporator fan motor.

Safety Warning:

Disconnect power to the refrigerator at the breaker panel before performing any repairs. Verify the power is off with a non-contact voltage tester. Lock-Out/Tag-Out (LOTO) procedures should be followed to prevent accidental re-energizing of the circuit. Be aware that capacitors may hold a charge even after the appliance is unplugged.

Prevention:

Regularly inspect the freezer compartment for excessive ice buildup. Ensure the refrigerator door seals are clean and intact to prevent air leaks. Avoid prolonged door openings.

Expert Tip:

To manually initiate a defrost cycle on many GE Café models, press and hold the “Freezer Up” and “Freezer Down” buttons simultaneously for approximately 5-10 seconds. The refrigerator will enter defrost mode. This can be helpful for diagnostic purposes.

Frequently Asked Questions

•How do I test the defrost thermostat?

The defrost thermostat should be closed (showing continuity) when cold. Use a multimeter to check for continuity while the thermostat is cold (below approximately 40 degrees Fahrenheit). If it's open when cold, it's defective.

•What voltage should I expect at the evaporator fan motor connector?

You should typically see 12V DC at the evaporator fan motor connector when the refrigerator is running and the fan is supposed to be operating. Use a multimeter to measure the voltage.

•Where is the evaporator fan motor located in my GE Café refrigerator?

The evaporator fan motor is located behind the evaporator cover inside the freezer compartment. It's typically mounted above the evaporator coil.

GE Café Refrigerator: Loud Thumping Noise During Defrost - Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•How do I test the defrost thermostat?

•What voltage should I expect at the evaporator fan motor connector?

•Where is the evaporator fan motor located in my GE Café refrigerator?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: